Thousands of people descended on central London on 31 March 1990 to demonstrate against the community charge - more commonly known as the poll tax - which was a fixed payment for all adults to their local authority.
The new tax, which replaced the rates system paid by all home owners based on the value of their property, proved to be unpopular in some quarters.
The day began with a peaceful march against the new government levy which saw up to 70,000 people take to the streets of central London.
Violence erupted in Trafalgar Square after a group of protesters involved in a sit-in at Whitehall, close to the Downing Street entrance, refused to move after requests from police and stewards.
Police arrested offenders, with the trouble spreading to Charing Cross Road, Pall Mall, Regent Street and Covent Garden.
Some 113 people were injured in the riots, including 45 police officers.
Cars were overturned and set alight during the mass protests, while some fire fighters who attempted to extinguish the blazes were reportedly hit with wood and stones.
A total of 340 people were arrested in the disturbances which prompted much of central London to be cordoned off.
David Meynell, who was in charge of the police operation, said a peaceful march had been "completely overshadowed by the actions of about 3,000 to 3,500 people in minority groups".
The violence led to many restaurants in and around London's popular West End to close early, while some shop windows were smashed and many businesses had their contents looted.
The London protests were the most famous, but rallies were held across the UK before and after that day and the levy's unpopularity was a factor in the downfall of the then prime minister, Margaret Thatcher, later that year.
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